1. Field of the Invention
The present invention relates to a sheet material conveying device for conveying a sheet material folded by being subjected to folding processingan, image forming apparatus equipped with the sheet material conveying device, and sheet processing device.
2. Description of the Related Art
Up to now, in a sheet post-processing device having a function of easily making a sheet material or a bundle of sheet materials (hereinafter simply referred to as a pamphlet) which has undergone folding processing, there is given, as a method of stacking prepared pamphlets, a stacking method of making a discharged pamphlet fall on a stacking portion and sequentially piling pamphlets.
Further, as in a large bookbinding device, there is given a stacking method of not piling but shifting discharged pamphlets in a transverse direction while sequentially conveying the pamphlets forward by means of a belt conveyor member.
However, in the case of the prior art as described above, there has been the following problem. In general, the vicinity on the folded side of a pamphlet is easier to swell compared with the opposite side. Thus, in the case where pamphlets are simply aligned in the folded side to be stacked, the uppermost stacking surface is not stable, stacking property is poor, and the number of stacked sheets is small to a staking space.
Further, also in the stacking method of shifting discharged pamphlets in a transverse direction while sequentially conveying the pamphlets forward by means of a belt conveyor member as in the large bookbinding device, a large stacking space is required.
Therefore, in a simple pamphlet stacking device used in an office space or the like as well, there is needed a device of an alternative stacking type which is small and inexpensive, which does not need a large area, and which enables mass stacking. Further, it is necessary to provide the pamphlet stacking device with an additional function that is inexpensive but corresponds to an application of an office.
The present invention has been made to solve the abovedescribed problem in the prior art, and has an object to provide a sheet material conveying device, image forming apparatus, and sheet processing device in which stacking property of a sheet material and a pamphlet can be improved without increasing a stacking space.
In order to achieve the above object, there is provided a sheet material conveying device being capable of conveying a folded sheet material that is discharged from an image forming apparatus for forming an image on a sheet material, including:
a first conveying path for discharging the folded sheet as it is;
a second conveying path branching out from the first conveying path;
a third conveying path, which branches out from the second conveying path and is connected with the first conveying path, for conveying the sheet material in an opposite direction to a conveying direction of the sheet material in the second conveying path;
first switching means for selectively guiding the sheet material to either the first conveying path or the second conveying path; and
second switching means for guiding the sheet material guided to the second conveying path to the third conveying path.
Further, a sheet material conveying device according to the present invention is characterized in that:
the second conveying path is provided with a pair of conveying rollers composed of two conveying rollers for conveying a sheet material to the second conveying path;
the second conveying path is curved; and
the conveying roller on the curved inner side of the pair of conveying rollers is a driving roller.
Further, a sheet material conveying device according to the present invention is characterized in that a nip of the pair of conveying rollers is in proximity to the curved inner side.
Further, a sheet material conveying device according to the present invention is characterized in that an inclination angle of stacking means for stacking the conveyed sheet material with respect to a horizontal plane is 20 to 45 decrees.
Further, a sheet material conveying device according to the present invention is characterized by further including detecting means for detecting a height of a sheet material stacked on stacking means for stacking the conveyed sheet material, in which
an initial operation for controlling a height of the stacking means is performed based on the detection result of the detecting means.
Further, a sheet material conveying device according to the present invention is characterized in that the initial operation is performed with a predetermined time interval.
Further, a sheet material conveying device according to the present invention is characterized in that the detecting means includes light emitting means for emitting light, light receiving means for receiving light emitted from the light emitting means, and light shielding means for shielding light which enters from the light emitting means to the light receiving means in accordance with the height of the stacking means.
Further, a sheet material conveying device according to the present invention is characterized in that the first switching means is alternately controlled in accordance with a predetermined operation procedure sent by the image forming apparatus.
Further, a sheet material conveying device according to the present invention is characterized by further including a sensor flag for detecting an angle of a straight line connecting at least two points on an upper surface or a sheet material on stacking means on which the conveyed sheet material is stacked, in which a switching operation of the first switching means is controlled based on the detection result of the sensor flag.
Further, a sheet material conveying device according to the present invention is characterized in that the sensor flag includes at least a first sensor flag arranged on the downstream side in the conveying direction of the sheet material on the stacking means and a second sensor flag arranged on the upstream side in the conveying direction of the sheet material on the stacking means; and
the sensor flag detects the angle of a straight line connecting at least two points on an upper surface of a sheet material on stacking means on which the conveyed sheet material is stacked based on detection signals output from the first sensor flag and the second sensor flag.
Further, a sheet material conveying device according to the present invention is characterized by further including a tip end detection sensor flag for detecting a tip end of a sheet material conveyed to the first conveying path, in which
a size of the conveyed sheet material is detected based on the detection time of the tip end detection sensor flag.
Further, a sheet material conveying device according to the present invention is characterized by further including:
a fourth conveying path for conveying a sheet material to the fist conveying path through folding processing means for conducting folding processing to the sheet material discharged from the image forming apparatus;
a fifth conveying path for conveying the sheet material discharged from the image forming apparatus to the first conveying path not through the folding processing means; and
third switching means for selectively guiding the sheet material to either the fourth conveying path or the fifth conveying path.
Further, a sheet material conveying device according to the present invention is characterized by further including:
a sixth conveying path branching out from the second conveying path;
processing means for processing a sheet material that is being conveyed through the sixth conveying path;
a seventh conveying path for conveying the sheet material discharged from the processing means to the first conveying path; and
fourth switching means for switching performing conveyance of the sheet material through the sixth conveying path and not performing conveyance thereof.
Further, a sheet material conveying device according to the present invention is characterized in that the processing means includes a Z-folding unit for Z-folding the sheet material.
Further, a sheet material conveying device according to the present invention is characterized in that the processing means includes a puncher unit for forming a punch hole in the sheet material.
Further, a sheet material conveying device according to the present invention is characterized in that the processing means includes a pasting processing unit for conducting pasting to the sheet material.
Further, a sheet material conveying device according to the present invention is characterized in that at least a part of a wall of a conveying path constituting the second conveying path consists of a conveying roller.
Further, a sheet material conveying device according to the present invention is characterized in that a stacking surface of stacking means for stacking the conveyed sheet material has a first angle that faces upward from the upstream side in the conveying direction of the sheet material to an inflection point positioned on the downstream side and has a second angle that faces downward compared with the first angle from the inflection point to the downstream side.
Further, a sheet material conveying device according to the present invention is characterized by further including:
an eighth conveying path for discharging a sheet material as it is which is discharged from the image forming apparatus, and conveying the sheet material to a post-processing device;
a ninth conveying path branching out from the eighth conveying path;
a tenth conveying path, which branches out from the ninth conveying path, for guiding the sheet material guided to the ninth conveying path to the eighth conveying path;
fifth switching means for selectively guiding the sheet material to either the eighth conveying path or the ninth conveying path;
sixth switching means for guiding the sheet material from the ninth conveying path to the tenth conveying path; and
an eleventh conveying path connected with the ninth conveying path and connected with the first conveying path.
Further, a sheet material conveying device according to the present invention is characterized in that the post-processing device is a stapling unit for conducting stapling processing to the sheet material.
Further, a sheet material conveying device according to the present invention is characterized by further including a twelfth conveying path for conveying the sheet material to the first conveying path through folding processing means for conducting folding processing to the sheet material discharged from the post-processing device.
Further, a sheet material conveying device according to the present invention is characterized by further including a thirteenth conveying path for conveying the sheet material to the first conveying path not through folding processing means for conducting folding processing to the sheet material discharged from the post-processing device.
Further, a sheet material conveying device according to the present invention is characterized by further including:
driving means for driving the entire device;
fixing means for detachably and attachably fixing the sheet material conveying device to the post-processing device;
communication means for conducting transfer of information between the sheet material conveying device and the post-processing device; and
drive control means for controlling a drive of the driving means based on the communication result of the communication means.
Further, an image forming apparatus according to the present invention is characterized by including image forming means for forming an image on a sheet material, in which the sheet material on which the image is formed is discharged to the sheet material conveying device as claimed in any of claims 1 to 23 by means of the image forming means.
Further, a sheet processing device according to the present invention is characterized by including:
a pair of folding rollers for sandwiching a loop portion formed in a sheet and folding the sheet;
a pair of discharge rollers for discharging a sheet;
a first conveying path for guiding the sheet folded by the pair of folding rollers to the pair of discharge rollers;
a pair of switchback rollers for conveying the sheet in a switchback manner;
a switching flapper for selectively guiding the sheet to the first conveying path or the pair of switchback rollers; and
a guide for guiding the sheet, which has been guided to the pair of switchback rollers by the switching flapper and conveyed in a switchback manner by the switchback rollers, so that the sheet joins the first conveying path.
Further, a sheet processing device according to the present invention is characterized in that the switching flapper guides second predetermined number of sheets, which is at least one, to the pair of switchback rollers every time the switching flapper guides first predetermined number of sheets, which is at least one, to the first conveying path.
Further, a sheet processing device according to the present invention is characterized by further including a control circuit for controlling the switching flapper and the switchback rollers.
Further, an image forming apparatus according to the present invention is characterized by including image forming means for forming an image on a sheet and the sheet processing device for conducting processing to the sheet on which the image is formed by the image forming means.
As described above, according to the present invention, the sheet material conveying device is arranged downstream of the post-processing device having a function of conducting saddle-stitch folding processing, and receives a pamphlet discharged from the post-processing device with the folded side as the leading end and selectively inverts the received pamphlet to stack it on the stacking means. Thus, alternate stacking is possible in which the folded sides of pamphlets are not superimposed. Accordingly, pamphlet stacking property can be improved, and an improvement in stacking amount can be realized.
Further, differently from a mode in which pamphlets are inverted to be alternately stacked by predetermined number of sheets, it is possible that: an actual inclination of the stacking surface is detected by a plurality of sensor flags for detecting heights of at least two parts on the upper surface of the pamphlet actually stacked on the stacking means; and based on the detection result, the pamphlet inversion is selectively controlled, whereby pamphlets having different swells are mixedly and alternately stacked.
Further, control is conducted in which the pamphlet inversion is alternately conducted for each job such as a printing job, for example, whereby job separation can be realized.
Further, the sheet material conveying device is provided with both the fourth conveying path and the twelfth conveying path, which are pamphlet receiving conveying paths for receiving a pamphlet from a post-processing device, and the fifth conveying path and the thirteenth conveying path, which are sheet material receiving conveying paths for receiving a not-folded sheet material from the post-processing device. Therefore, in the case where the sheet material conveying device is connected with the post-processing device provided with both a pamphlet discharging function of conducting saddle-stitch folding processing to the sheet material received from the image forming apparatus and discharging the sheet material with the folded side thereof as the leading end and a sheet discharging function of not conducting saddle-stitch folding processing to the sheet material and discharging the sheet material as it is, the sheet material conveying device can also be used as a mass stacker that realizes an increase in stacking amount of a sheet material in addition to the use as a pamphlet alternate stacking device.
Further, a large area can be secured in a lower space. Thus, the sixth conveying path branching out from the midway of the second conveying path and the processing means for conducting sheet folding (for example, Z-folding or C-folding), pastebinding, punching, or the like with respect to a sheet bundle, which is positioned downstream thereof, can be additionally provided.
The sheet material conveying device is provided with the seventh conveying path for conveying a sheet material processed by the processing means to the first conveying path, and thus, new sheet processing can be realized in addition to the pamphlet stacking function.
Further, when the sheet material conveying device is provided with sheet stacking means having a frame body which is different from standard stacking means in the above-mentioned area, further mass stacking is enabled.
Furthermore, the sheet material conveying device is arranged downstream of the post-processing device, and is provided with the fixing means, the communication means with the post-processing device, the driving means for driving the entire device, and the drive control means for controlling the driving means, thereby being a unit detachable and attachable with respect to the post-processing device. Thus, the sheet material conveying device can be applied to various kinds of post-processing devices.
As described above, according to the present invention, there can be switched the case where the folded sheet material is discharged to the stacking means from the first conveying path and the case where the folded sheet material is inverted through the second conveying path and the third conveying path to be discharged. Thus, the folded sides of the pamphlets can be appropriately combined to make the pamphlets discharged onto the stacking means. Therefore, pamphlet stacking property can be improved.